The present invention pertains generally to structural members and, more particularly, to a vehicle structure having an integral node.
In the field of motor vehicle design, it is highly desirable to construct a modular vehicle including a subframe adaptable for use with a variety of aesthetically pleasing outer panels. Additionally, the use of extruded tubular sections within the construct of the subframe greatly enhances the strength and durability of the frame without drastically increasing the weight and cost.
Unfortunately, many manufacturers have had difficulty reliably interconnecting individual tubular frame components to form a dimensionally correct and structurally robust vehicle frame. Accordingly, some manufacturers have implemented separate connectors, called nodes, to facilitate the joining process. The separate nodes are typically aluminum alloy castings having a plurality of apertures for receipt of tubular frame components. Due to the relative difficulty of welding aluminum alloys, cast nodes are especially prevalent in joints structurally interconnecting stamped or extruded aluminum components. As would be expected, the use of separate nodes is both costly and time consuming. Therefore, a need in the relevant art exists for an apparatus and method for interconnecting structural members.
Accordingly, it is an object of the present invention to provide an improved vehicle body construction exhibiting the advantages of a tubular construction without the need for separate connectors such as cast nodes.
It is another object of the present invention to provide a structural component including an integrally hydroformed node for use in a vehicle structure having improved strength and dimensional accuracy.
In accordance with the present invention, a fluid formed node is provided to connect structure in an automotive vehicle. Another aspect of the present invention includes a method of forming a structural interconnection including the steps of placing a first member, having an internal cavity in a die, pressurizing the internal cavity to form a node integral with and protruding from the first member, disposing the node within an aperture of a second member, and coupling the second member to the node.
The node of the present invention is advantageous over conventional construction in that the present invention provides an integrally formed attachment location economically created through the use of hydroforming. Additionally, structures incorporating the node of the present invention exhibit superior dimensional stability and structural integrity as compared to the structures previously described. Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.